Restrict deep nesting of configfiles

There is no point in restricting the number of included config-
files, but there is a point in restricting the nestinglevel
of configfiles: to avoid recursive inclusions. This is easily
achieved by decrementing the static nesting-variable upon exit
from cgit_read_config().

Also fix some whitespace breakage.

Signed-off-by: Lars Hjemli <hjemli@gmail.com>

1 files changed, 4 insertions, 2 deletions

diff --git a/parsing.c b/parsing.c
index 8e15e5a..36b0f0c 100644
--- a/parsing.c
+++ b/parsing.c
@@ -9,135 +9,137 @@
 #include "cgit.h"
 
 int next_char(FILE *f)
 {
 	int c = fgetc(f);
 	if (c=='\r') {
 		c = fgetc(f);
 		if (c!='\n') {
 			ungetc(c, f);
 			c = '\r';
 		}
 	}
 	return c;
 }
 
 void skip_line(FILE *f)
 {
 	int c;
 
 	while((c=next_char(f)) && c!='\n' && c!=EOF)
 		;
 }
 
 int read_config_line(FILE *f, char *line, const char **value, int bufsize)
 {
 	int i = 0, isname = 0;
 
 	*value = NULL;
 	while(i<bufsize-1) {
 		int c = next_char(f);
 		if (!isname && (c=='#' || c==';')) {
 			skip_line(f);
 			continue;
 		}
 		if (!isname && isspace(c))
 			continue;
 
 		if (c=='=' && !*value) {
 			line[i] = 0;
 			*value = &line[i+1];
 		} else if (c=='\n' && !isname) {
 			i = 0;
 			continue;
 		} else if (c=='\n' || c==EOF) {
 			line[i] = 0;
 			break;
 		} else {
 			line[i]=c;
 		}
 		isname = 1;
 		i++;
 	}
 	line[i+1] = 0;
 	return i;
 }
 
 int cgit_read_config(const char *filename, configfn fn)
 {
 	static int nesting;
 	int len;
 	char line[256];
 	const char *value;
 	FILE *f;
 
-	/* cancel the reading of yet another configfile after 16 invocations */
-	if (nesting++ > 16)
+	/* cancel deeply nested include-commands */
+	if (nesting > 8)
 		return -1;
 	if (!(f = fopen(filename, "r")))
 		return -1;
+	nesting++;
 	while((len = read_config_line(f, line, &value, sizeof(line))) > 0)
 		(*fn)(line, value);
+	nesting--;
 	fclose(f);
 	return 0;
 }
 
 char *convert_query_hexchar(char *txt)
 {
 	int d1, d2;
 	if (strlen(txt) < 3) {
 		*txt = '\0';
 		return txt-1;
 	}
 	d1 = hextoint(*(txt+1));
 	d2 = hextoint(*(txt+2));
 	if (d1<0 || d2<0) {
 		strcpy(txt, txt+3);
 		return txt-1;
 	} else {
 		*txt = d1 * 16 + d2;
 		strcpy(txt+1, txt+3);
 		return txt;
 	}
 }
 
 int cgit_parse_query(char *txt, configfn fn)
 {
 	char *t, *value = NULL, c;
 
 	if (!txt)
 		return 0;
 
 	t = txt = xstrdup(txt);
  
 	while((c=*t) != '\0') {
 		if (c=='=') {
 			*t = '\0';
 			value = t+1;
 		} else if (c=='+') {
 			*t = ' ';
 		} else if (c=='%') {
 			t = convert_query_hexchar(t);
 		} else if (c=='&') {
 			*t = '\0';
 			(*fn)(txt, value);
 			txt = t+1;
 			value = NULL;
 		}
 		t++;
 	}
 	if (t!=txt)
 		(*fn)(txt, value);
 	return 0;
 }
 
 char *substr(const char *head, const char *tail)
 {
 	char *buf;
 
 	buf = xmalloc(tail - head + 1);
 	strncpy(buf, head, tail - head);
 	buf[tail - head] = '\0';
 	return buf;
 }
 
 struct commitinfo *cgit_parse_commit(struct commit *commit)